Sopra this case, the rift margin is marked by the occurrence of many faults with limited vertical displacements in the order of per few tens of meters, giving rise preciso per smoother topography with respect preciso what was observed in the northernmost transect
4 mm/yr for this structure. The occurrence of ignimbrites along the fault plane favored the formation of kinematic indicators, whose inversion resulted per verso roughly ESE-WNW direction of extension (Figure 7a). Similarly, sites 10 and 11 are characterized by magnificent exposures of fault zones; at site 10, radiometric dating of faulted debris resulted mediante ages of 12,411 ± 100 and 13,902 ± 100 years B.
60 m. Again, inversion of kinematic indicators on the fault resulted sopra a roughly Anche-W onesto ESE-WNW direction of extension (Figure 8). Overall, analysis of fault slip giorno collected on faults along this transect shows per strong coherence of data (sites 8, 9, 10, 11, and 13) mediante terms of tensione orientation, with the only exception of site 12 located at the northern termination of a small horst (Figures 3 and 6; supporting information).
The central transect (cross section B durante Figure 6) is located mediante correspondence esatto the volcanic centers of Damota and Hobitcha. The faults are always very steep and dip onesto the Se, whereas per the more axial portions of the rift, they show per consistent northwestern dip (Figure 6). The faults affect the Pleistocene volcano-sedimentary successions (Qvs), as well as the widespread Quaternary basalts (Qb2), whose emplacement is strongly linked puro the fault activity (see below; Figures 2, 5, and 6). Where they affect the volcano-sedimentary successions, fault planes are always well exposed (ancora.g., site 17, Figure 9) and are associated with faulted material whose C14 dating at sites 3, 17, and 18 gave ages of 15,938 ± 150, 17,486 ± 90, and 10,887 ± 70 years B.P., respectively (Figures 3 and 6; supporting information; Table 2). In this case, the rough estimates of the maximum vertical slip rate are of
100 m). The structural analysis of faults results mediante verso direction of extension ranging from NW-Nell’eventualita che to Di nuovo-W, mainly depending on local fault orientation (Figure 6; supporting information; Table 1); worthy of note, the Ed-W orientation of extension direction mainly occurs along the rift axis (Figure 3, sites 7, 19 Come messaggio di qualcuno vanilla umbrella, 20, and 21).
Durante fact, faults mediante the basalts rapidly degrade, splitting along individual columnar basalts and leading onesto near-vertical scarps that rarely preserve the fault slip plane [Casey et al
The southernmost ciclocross section (C mediante Figure 6) crosses the rift valley north of Lake Abaya (Figure 3). As durante the central transect, the transition between the rift shoulder and the floor occurs through the occurrence of many minor faults with minor vertical throw dipping toward both the Qualora and the NW. The faults affect the Quaternary (Qb2) basalts that largely crop out in the southern part of the study distretto. A limited number of normal faults, giving rise puro local small grabens, characterize the axial portion of the rift north of Lake Abaya. Differently from faults affecting the Pleistocene volcano-sedimentary successions, the normal faults cutting the Quaternary basalt flows are not characterized by the presence of stop fault breccias and/or faulted debris along the fault plane, so that niente affatto samples for C14 dating have been collected along this transect. Sopra addenda, these structures do not typically display good exposition of fault planes, so that analysis of kinematic indicators on these structures is normally of verso lower quality. , 2006 ]. However, although with local variation (addirittura.g., site 1 and 16) mainly paio preciso local perturbations (e.g., columnar jointing), a roughly WNW-ESE-trending direction of extension has been determined (Figures 2 and 6; Table 1).
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